At first glance, today's Quinnipiac poll makes the 2013 mayoral campaign look like a two-tier race, with City Council Speaker Christine Quinn in front and everyone else bunched up behind her.

Her nearest rival is former city comptroller Bill Thompson, who has 13 percent, followed by Public Advocate Bill de Blasio at 10 percent.

With the important disclaimer that it's silly to try to draw definitive conclusions from polling this far out, one thing that jumps out is that Thompson, the Democratic nominee in the last mayoral election, seems to have lots of room to improve among African-American Democrats, whose preferences in the poll break down like this:

If Thompson attracts a comparable level of black support it would set him up as the leading alternative to Quinn, the de facto establishment candidate, possibly setting the stage for Quinn-Thompson runoff if neither candidate gets at least 40 percent of the vote in the primary.